Composition and Process for Preparing NIR Shielding Masterbatch and NIR Shielding Masterbatch and Application Thereof

ABSTRACT

Disclosed herein is a method for preparing a near infrared shielding masterbatch. The method includes the steps of preparing and compounding a composition, and then pelletizing the compounded composition. The composition includes at least one metallic ionic compound powder in an amount of about 1-25 wt %, a cross-linking agent in an amount of about 0.1-5 wt %, a thermoplastic polymer in an amount of about 67-98.7 wt %, an initiator in an amount of about 0.1-1 wt %, and a dispersing agent in an amount of about 0.1-2 wt %.

RELATED APPLICATIONS

This application claims priority to Taiwan application no. 98143744,filed Dec. 18, 2009, the entirety of which is incorporated herein byreference.

BACKGROUND

1. Field of Invention

The present invention relates to a near-infrared shielding material.

2. Description of Related Art

Textiles are widely applied in our daily life, and functional textileswith additional functionality are becoming the main research anddevelopment interest of the textile industry.

Conventionally, to endow textile with an additional functionality, thesurfaces of the fabrics or fibers are post-treated or -processed withactive ingredient(s) so as to obtain functional textiles or fibers.Problems faced by functional textiles produced thereby include poorfastness to washing, less air permeability, and harsh hand-feel.Besides, the functional materials tend to fall-off from the functionalfabrics thereby impairing the functionality endowed by the functionalmaterials.

In contrast to the post-treatment of the fabrics, modifying the polymersso as to produce polymers with the additional functionality attractsmore and more research interest. However, many challenges remainunsolved in the attempt to physically and/or chemically modify apolymeric material. For example, factors to be taken into account whilephysically mixing the functional material with the polymeric materialinclude: the homogeneity of the resultant mixture and the stability ofthe mixture. In addition, the amount of the functional material alsoplays an important role, since the functional material, in aninsufficient amount, may not be able to endow the final fabrics with thedesired functionality, whereas the functional material, in an excessamount, may jeopardize the original properties of the polymericmaterial, and thereby renders the spinning and following treatment(s)inoperable.

In view of the foregoing, although polymer modification is the mainresearch target of the textile industry, each functional material willface its own challenge in the modification process.

SUMMARY

The following presents a simplified summary of the disclosure in orderto provide a basic understanding to the reader. This summary is not anextensive overview of the disclosure and it does not identifykey/critical elements of the present invention or delineate the scope ofthe present invention. Its sole purpose is to present some conceptsdisclosed herein in a simplified form as a prelude to the more detaileddescription that is presented later.

In one aspect, the present invention is directed to a composition forpreparing a near-infrared shielding masterbatch, which can be used tomanufacture films and/or fibers that exhibit near-infrared shielding andthermal shielding functionalities.

According to one embodiment of the present invention, the compositionincludes at least one metallic ionic compound powder in an amount ofabout 1-25 wt %, a cross-linking agent in an amount of about 0.1-5 wt %,a thermoplastic polymer in an amount of about 67-98.7 wt %, an initiatorin an amount of about 0.1-1 wt %, and a dispersing agent in an amount ofabout 0.1-2 wt % in the composition. The metallic ionic compound powdercan be at least one of: barium sulfate powder, ferrious oxide (Fe₂O₃)powder, copper oxide (CuO) powder, iridium dioxide (IrO₂) powder andzinc oxide (ZnO) powder.

In another aspect, the present invention is directed to a method forpreparing a near-infrared shielding masterbatch. The method can be used,in conjunction with the composition according to the above-describedaspect of the present invention, to prepare a masterbatch for use in aspinning process.

According to one embodiment of the present invention, the methodcomprises the steps as follows. First, a composition according to theabove-described aspect/embodiment is provided. Thereafter, thecomposition is compounded at a compounding temperature of about 220-270°C. for about 1-20 minutes. During the compounding process, thethermoplastic polymer is melted, and the cross-linking agent wouldcross-link with the molten thermoplastic polymer, whereby the metallicionic compound powder would distribute across the cross-linkedthermoplastic polymer. Afterwards, the compounded composition ispelletized to obtain the near-infrared shielding masterbatch.

In still another aspect, the present invention is directed to anear-infrared shielding masterbatch that is prepared from thecomposition and by the method according to the above-describedaspects/embodiments of the present invention. Such near-infraredshielding masterbatch contains a greater amount of the metallic ioniccompound powder as comparing with the comparative example presentedhereinbelow, and is suitable for use in the spinning process.

According to one embodiment of the present invention, the near-infraredshielding masterbatch comprises: a cross-linked thermoplastic polymerand at least one metallic ionic compound powder distributing across thecross-linked thermoplastic polymer. The metallic ionic compound powderis at least one of: barium sulfate powder, ferrious oxide powder, copperoxide powder, iridium dioxide powder and zinc oxide powder. The weightratio of the cross-linked thermoplastic polymer to the metallic ioniccompound powder is about 2.8:1 to about 98.8:1.

In yet another aspect, the present invention is directed to anear-infrared shielding article comprising a near-infrared shieldingpart manufactured from the near-infrared shielding masterbatch accordingto the above-described aspects/embodiments of the present invention.

In still another aspect, the present invention is directed to a methodfor preparing a near-infrared shielding fiber. The method can be used,in conjunction with the masterbatch according to the above-describedaspect of the present invention, to prepare a near-infrared shieldingfiber containing a greater amount of metallic ionic compound powder ascomparing with the comparative example presented hereinbelow.

According to one embodiment of the present invention, the methodcomprises the steps as follows. First, a near-infrared shieldingmasterbatch according to the above-described aspect/embodiment isprovided. Thereafter, the near-infrared shielding masterbatch is meltspinned with a spinning temperature of about 180° C. to about 300° C., afeed speed of about 5 rpm to 30 rpm, and a regulating wheel speed ofabout 400 m/min to about 3500 m/min.

Many of the attendant features will be more readily appreciated as thesame becomes better understood by reference to the following detaileddescription considered in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present description will be better understood from the followingdetailed description read in light of the accompanying drawings,wherein:

FIG. 1 is a diagram illustrating the temperature profile of a filmaccording to one working example of the present invention;

FIG. 2 is a diagram illustrating the temperature profile of a filmaccording to another working example of the present invention;

FIG. 3 is a near-infrared spectrogram of a film according to one workingexample of the present invention;

FIGS. 4A-4C are optical micrographs of core-sheath fibers according toworking examples of the present invention;

FIG. 5 is a diagram illustrating the temperature profile of a fabricaccording to one working example of the present invention;

FIG. 6 is a diagram illustrating the temperature profile of a fabricaccording to another working example of the present invention; and

FIG. 7 is a near-infrared spectrogram of a fabric according to oneworking example of the present invention; and

FIG. 8 is a diagram illustrating the temperature profile of a fabricaccording to another working example of the present invention.

DETAILED DESCRIPTION

The detailed description provided below in connection with the appendeddrawings is intended as a description of the present examples and is notintended to represent the only forms in which the present example may beconstructed or utilized. The description sets forth the functions of theexample and the sequence of steps for constructing and operating theexample. However, the same or equivalent functions and sequences may beaccomplished by different examples.

Factors to be taken into account while manufacturing a functionalmasterbatch by using a modifying agent (functional material) include theefficacy of the functional material (or the resultant functionalproduct), the compatibility between the functional material and thethermoplastic material, the effects the functional material imposing onthe thermoplastic material, the processability of the resultantfunctional masterbatch and/or product, and the benefit-cost ratio of thefunctional product.

In view of the foregoing and other factors, a first aspect of thepresent disclosure is directed to a composition for preparing anear-infrared shielding masterbatch. Generally, the composition forpreparing the near-infrared shielding masterbatch comprises: a metallicionic compound powder, a cross-linking agent, a thermoplastic polymer,an initiator and a dispersing agent.

According to embodiments of the present invention, the metallic ioniccompound powder may be at least one of: barium sulfate powder, ferriousoxide powder, copper oxide powder, iridium dioxide powder or zinc oxidepowder. Such powders of metal oxides or metal salts are able to reflectand/or refract light, especially near IR. According to the principlesand spirits of the present invention, the amount of the metal oxidesand/or metal salts of the metallic ionic compound powder are notparticularly limited and can be adjusted as desired. Specifically, eachof the metal oxides and metal salts may exhibit different opticalproperties, and hence, the amount of any given species in the metallicionic compound powder may be adjusted depending on the opticalproperties to be achieved. Moreover, the metallic ionic compound powdermay comprise additional powders of metal oxides (such as titaniumdioxide powder) and/or metal salts so as to modify the optical propertyof the resultant near-infrared shielding masterbatch.

However, the metallic ionic compound powder is an inorganic materialthat usually has poor compatibility with the thermoplastic polymer. Assuch, the metallic ionic compound powder tends to aggregate within thethermoplastic polymer, even with the addition of a dispersing agent. Theissue of the poor compatibility limits not only the amount of themetallic ionic compound powder to be used, but also the near-infraredshielding efficacy that the product may exhibit.

Hence, according to this aspect of the present invention, thecomposition comprises a cross-linking agent, so that by cross-linking,the dispersity and uniformity of the metallic ionic compound powderwithin the thermoplastic polymer may be improved, and the aggregation ofthe metallic ionic compound powder may be alleviated. In addition, themetallic ionic compound powder distributing within the cross-linkednetworked structure may form a multilayered reflective mirror so as toreflect the near-infrared source.

Moreover, as can be evidenced by the working examples providedhereinbelow, the cross-linking technique may also increase the amount ofthe metallic ionic compound powder relative to the thermoplasticpolymer. Therefore, the near-infrared shielding masterbatch and thenear-infrared shielding film/fiber provided herein may exhibit theefficacies of near-infrared shielding and thermal shielding.

Further, as can be appreciated by those with ordinary skill in the art,increasing the amount of the inorganic modifying agent of themasterbatch may usually jeopardize the spinnability of the masterbatch.However, the near-infrared shielding masterbatch prepared by the methodprovided herein may comprise higher amount of metallic ionic compoundpowder (as comparing with conventional ones) and is still suitable forthe spinning process.

Generally, the composition according to the present disclosure maycomprises a metallic ionic compound powder present in an amount of about1-25 wt %. For example, the weight percent of the metallic ioniccompound powder is about 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5,7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14,14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, 20, 20.5, 21,21.5, 22, 22.5, 23, 23.5, 24, 24.5 or 25%.

According to optional embodiments of the present invention, the metallicionic compound powder may have a diameter in the micron or submicronorder, thereby further improving the uniformity of the metallic ioniccompound powder within the thermoplastic polymer. Generally, thediameter of the metallic ionic compound powder may be about 0.1-10 μm,for example, about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3,4, 5, 6, 7, 8, 9 or 10 μm.

According to embodiments of the present disclosure, the cross-linkingagent may be a diallyl compound or a triallyl compound.

Illustrative examples of diallyl compounds include, but are not limitedto, diallyl phthalate (DAP), diallyl succinate (DASu), andN,N′-diallyltartramide (DATD).

Illustrative examples of triallyl compounds include, but are not limitedto, triallylamine, triacryloylhexahydro-1,3,5-triazine (TAT), triallyltrimesate (TAM), triallyl cyanurate (TAC), triallyl isocynaurate (TAIC),and triallyl-ammoniumcyanurate. For example, TAT is used in an exampleprovided hereinafter.

According to various embodiments of the present invention, the weightpercent of the cross-linking agent of the composition for preparing anear-infrared shielding masterbatch is about 0.1% to about 5%.Specifically, the weight percent of the cross-linking agent of the totalcomposition may be about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1,1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5,2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4,4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9 or 5%.

The addition of the initiator in the composition may facilitate thecross-linking reaction. The weight percent of the cross-linking agent ofthe composition for preparing a near-infrared shielding masterbatch isabout 0.01% to about 1%; more specifically, about 0.01, 0.02, 0.03,0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7,0.8, 0.9, or 1%.

The choice of the initiator often depends on the cross-linking agent tobe used. Illustrative examples of initiators include, but are notlimited to, potassium persulfate, azobisisobutyronitrile (AIBN), andbenzyl dimethyl ketal (BDK).

The dispersing agent may assist in uniform distribution of theconstituents within the composition. Generally, the dispersing agent maybe C₁₅₋₃₈ alkanes, C₁₅₋₃₈ esters, C₁₅₋₃₈ organic acids, and mixturesthereof. In the examples presented hereinafter, the dispersing agentused is paraffin.

According to various embodiments of the present invention, the weightpercent of the dispersing agent of the composition for preparing anear-infrared shielding masterbatch is about 0.1% to about 2%.Specifically, the weight percent of the dispersing agent of the totalcomposition may be about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1,1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9 or 2%.

Any synthetic thermoplastic polymer may be used according to theembodiments of the present invention; particularly those suitable forspinning process. Examples of the thermoplastic polymer may include, butare not limited to, polyester, polyamide, and polypropylene (PP).

Specifically, illustrative examples of polyester may includepolyethylene terephthalate (PET), polybutylene terephthalate (PBT), andpolytrimethylene terephthalate (PTT). Polyamide is a synthetic polymerfamily including, but not limited to, nylon 6, nylon 6.6 and nylon 6.10.

The weight percent of the thermoplastic polymer of the total compositionis about 67% to about 98.7%. Specifically, the weight percent of thethermoplastic polymer of the total composition may be about 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 98.7%.

In another aspect, the present disclosure is directed to a method forpreparing a near-infrared shielding masterbatch using the compositionprovided in the above-mentioned aspect/embodiments.

According to one embodiment of the present disclosure, the methodcomprises the steps as follows. First, the composition according toabove-mentioned aspect/embodiments is prepared. Then, the composition iscompounded to melt the thermoplastic polymer whereby the meltedthermoplastic polymer is cross-linked by the cross-linking agent, andthe metallic ionic compound powder is dispersed in the cross-linkedthermoplastic. Generally, the compounding step is performed for about1-20 minutes, and a compounding temperature is about 220-270° C.Afterwards, the cross-linked thermoplastic is pelletized to obtain thenear-infrared shielding masterbatch.

According to one optional embodiment, the method for preparing thecomposition comprises the steps as follows. First, the thermoplasticpolymer and the cross-linking agent are admixed to form an admixture.Then, the initiator is added into the admixture. Afterward, thedispersing agent and the metallic ionic compound powder are added intothe admixture, thereby obtaining the composition ready for compounding.The problem of the agglomeration of the metallic ionic compound powdercan be further reduced by preparing the composition in accordance withthis specified order.

In some embodiments, the mixing steps may be carried out in any suitablecontainer or mixer. For example, the composition can be mixed by a 3Dmixer so as to further facilitate the homogeneity of the composition.Thereafter, the composition is fed into an extruder for compoundingand/or pelletizing the masterbatch. Alternatively, the mixing steps maybe done in the extruder.

The compounding and pelletizing steps are carried out in the extruder.Any customary extruders and extrusion techniques for preparingmasterbatches may be employed according to the embodiments of thepresent invention. A well-known compounding apparatus may include, butis not limited to, a twin screw extruder. During the operation of thetwin screw extruder, the process parameters may be adjusted depending onthe actual situation. For example, in one optional embodiment, the speedof the screw member may be adjusted to about 200-350 rpm.

In still another aspect, the present invention is directed to anear-infrared shielding masterbatch that is prepared from thecomposition and by the method according to the above-describedaspects/embodiments of the present invention.

Such near-infrared shielding masterbatch contains a greater amount ofthe metallic ionic compound powder as comparing with the comparativeexample presented hereinbelow, and is suitable for use in the spinningpress.

According to one embodiment of the present invention, the near-infraredshielding masterbatch comprises: a cross-linked thermoplastic polymerand at least one metallic ionic compound powder distributing across thecross-linked thermoplastic polymer. The metallic ionic compound powderis at least one of: barium sulfate powder, ferrious oxide powder, copperoxide powder, iridium dioxide powder and zinc oxide powder. The weightratio of the cross-linked thermoplastic polymer to the metallic ioniccompound powder is about 2.8:1 to about 98.8:1. As such, the resultantshielding masterbatch comprises thermoplastic polymer cross-linked bythe cross-linking agent and metallic ionic compound powder distributedacross the cross-linked thermoplastic polymer.

According to various embodiment of the present invention, in thenear-infrared shielding masterbatch, the weight ratio of thecross-linked thermoplastic polymer to the metallic ionic compound powderand is about 2.8:1 to about 98.8:1.

For example, if the weight percent of the metallic ionic compound powderbased on the total composition is about 1%, the sum of the weightpercents of the thermoplastic polymer and the cross-linking agent isabout 98.8%. In this case, the weight ratio of the cross-linkedthermoplastic polymer to the metallic ionic compound powder is about98.8:1. Similarly, if the weight percent of the metallic ionic compoundpowder based on the total composition is about 25%, the sum of theweight percents of the thermoplastic polymer and the cross-linking agentis about 72% at maximum. In this case, the weight ratio of thecross-linked thermoplastic polymer to the metallic ionic compound powderis about 72:25 (that is, about 2.8:1).

As described hereinabove, the near-infrared shielding masterbatch isprepared from the composition according to the aspect/embodiments of thepresent invention. Hence, the constituents making up the composition andweight ratios thereof are disclosed in the above-described embodiments.Accordingly, for the sake of brevity, a description of the compositionfor preparing the near-infrared shielding masterbatch is not repeated.

In another aspect, the present invention is directed to a near-infraredshielding article, which comprises a near-infrared shielding part thatis prepared from the near-infrared shielding masterbatch according tothe above-mentioned aspect/embodiments of the present invention.

In various optional embodiments, the near-infrared shielding part can bemanufactured in a form of a fiber, a filament, a yarn, a textile, afilm, a sheet, or a chip.

According to one optional embodiment, the near-infrared shieldingarticle can be manufactured into a core-sheath fiber. Generally, acore-sheath fiber comprises a core fiber and a sheath fiber, wherein thecore fiber can be concentrically or eccentrically arranged. For example,the near infrared shielding masterbatch can be used to prepare the corefiber, and thereby, the resultant core-sheath fiber can exhibit thenear-infrared shielding functionality. Test results show that suchcore-sheath fiber has satisfactory fiber strength and washing fastness.

In optional embodiments, the core fiber and the sheath fiber may have acore/sheath ratio of about 1:1 to about 3:1. As used herein, thecore/sheath ratio is the weight ratio of the core fiber to the sheathfiber. For example, the core/sheath ratio of the core-sheath fiberprovided herein may be about 1:1, 1.5:1, 2:1, 2.5:1 or 3:1.

According to another optional embodiment, the near-infrared shieldingarticle can be manufactured into a sea-island fiber. Generally, asea-island fiber comprises a sea component fiber and a plurality ofisland component fibers embedded in the sea component fiber. In oneexample, the near infrared shielding masterbatch can be used to preparethe island component fibers.

In yet another aspect, the present invention is directed to a method forpreparing a near-infrared shielding fiber.

According to one embodiment of the present invention, the methodcomprises the steps as follows. First, the near-infrared shieldingmasterbatch according to the above-mentioned aspect/embodiments isprepared. Then, the masterbatch undergoes a melt spinning process toproduce a near-infrared shielding fiber. Generally, the melt spinningmay be carried out at the following conditions: a melt spinningtemperature of about 180° C. to 300° C.; masterbatch feed speed of about5 rpm to about 30 rpm; and godet wheel rotate speed of about 400 m/minto about 3500 m/min.

For example, the melt spinning temperature can be about 180, 190, 200,210, 220, 230, 240, 250, 260, 270, 280, 290 or 300° C. According to oneoptional embodiment of the present invention, the melt spinningtemperature is about 240° C. to 275° C.

The masterbatch feed speed can be about 5, 6, 7, 8, 9, 10, 11, 12, 13,14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29 or 30rpm. According to one optional embodiment of the present invention, themasterbatch feed speed is about 15 rpm to 30 rpm.

Some working examples according to embodiments of the present inventionare provided hereinafter, wherein the constituents making up thecomposition and weight ratios thereof were adjusted to obtain variousmasterbatches. The masterbatches were then manufactured into film(s)and/or fiber(s), and the near-infrared transmittance thereof and thetemperature profiles of an enclosed space shielded thereby wereanalyzed.

In the working examples present hereinbelow, the sample was analyzed bya near-infrared spectrometer (Model: Jasco V-570 UV/Vis/NIRSpectrophotometer) to investigate the light transmittance of the sampleover the wavelength range of about 900-2500 nm.

The method for measuring the temperature profile of an enclosed spaceshield by the sample being irradiated by near-infrared includes thesteps as follows. A 10 cm×10 cm sample (ex., the film or fabric) was putin an enclosed container, and the initial temperature of this containerwas measured to obtain the reference temperature. Then, the sample wasirradiated by a near infrared lamp (wavelength range: 800-2500 nm), andthe temperature within the enclosed container was measured and recordedevery five minutes. As used herein, the term “temperature rise” of thecontainer at a given time is defined as the difference between thetemperature measured at that time and the reference temperature.

Experiment 1

In Experiment 1, various near-infrared shielding masterbatches wereprepared in accordance with the method described hereinabove where theamount of the cross-linking agent was adjusted in each near-infraredshielding masterbatch. The masterbatch was then made into the form of afilm having a thickness of about 0.01 cm, and the temperature profile ofthe container shielded thereby was recorded.

In this example, the metallic ionic compound powder comprised about 5parts by weight of a mixture ferric oxide (Fe₂O₃) and cupric oxide(CuO), about 1 part by weight of iridium dioxide powder, about 2 partsby weight of barium sulfate powder, and about 2 parts by weight of zincoxide powder. In this experiment, TAIC was used as the cross-linkingagent and the weight ratio thereof is summarized in Table 1, about 0.1wt % of BDK was used as the initiator, about 0.5 wt % of paraffin wasused as the dispersing agent, and the thermoplastic polymer used wasnylon 6.

The weight ratios of the metallic ionic compound powder and thecross-linking agent of each working and comparative example inExperiment 1 are summarized in Table 1, and the temperature rise of eachexample against time is illustrated in the curve diagram of FIG. 1.

TABLE 1 Metallic ionic Cross-linking Temperature compound powder agentrise after 1 hr (wt %) (wt %) (° C.) Working 5 1 9.7 example 1A Working5 2 10.2 example 1B Comparative 5 0 10.8 example 1 Pure nylon 0 0 13.3

Reference is made to Table 1 and FIG. 1. As shown in Table 1, afterbeing irradiated by the near-infrared lamp for one hour, the temperaturerise in the container shielded by the pure nylon film was about 13.3° C.(38.3° C.−25° C.=13.3° C.). In comparison, in the comparative example 1(containing about 5 wt % of the metal compound powder but nocross-linking agent), the temperature rise after one hour was about10.8° C., which was 2.5° C. less than that of the pure nylon film.Further, the data showed that the temperature rise can be furtherreduced in the working examples. Take working example 1A as an example,the temperature rise after one hour was about 9.7° C., which was 3.6° C.less than that of the pure nylon film and 1.1° C. less than that of thecomparative example 1. The data present in Table 1 and FIG. 1 show thatthe films prepared from the near infrared shielding masterbatchaccording to the present invention exhibit thermal shieldingfunctionality.

Experiment 2

In Experiments, the constituents making up the composition and weightratios thereof are substantially similar to that of Experiment 1, exceptthat the weight ratio of the metallic ionic compound powder was variedand the weight ratio of the cross-linking agent was fixed at about 1 wt%. The resultant near-infrared shielding masterbatch was then made intothe form of a film having a thickness of about 0.01 cm. Thereafter, thenear-infrared transmittance of the film was analyzed, and thetemperature profile of the container shielded thereby was recorded.

The weight ratios of the metallic ionic compound powder, the temperaturerise and near-infrared transmittance of each working and comparativeexample in Experiment 2 are summarized in Table 2. The temperatureprofile of each container shielded by the films is illustrated by thecurve diagram of FIG. 2. The near-infrared spectrogram (over the rangeof 900-2500 nm) of some working examples of this experiment is presentin FIG. 3.

TABLE 2 Metallic ionic Temperature NIR compound powder rise after 1 hrtransmittance (wt %) (° C.) (%) Working 1 11.3 15-40 example 2A Working3 10.6 14-37 example 2B Working 5 9.7 3-7 example 2C Working 7 9.3 2-5example 2D Working 10 8.7 2-7 example 2E Working 15 8 1-5 example 2FWorking 20 7.5 1-5 example 2G Working 25 7.2 1-4 example 2H Comparative15 — — example 2* Pure nylon 0 13.3 55-70 *Without cross-linking agent.

As shown in Table 2 and FIG. 2, the thermal shielding efficacy of thenear-infrared shielding film increases as the amount of the metallicionic compound powder increases. According to the present invention, thethermal shielding efficacy of a sample is evidenced by less temperaturerise of the container shielded by the sample. Tale working example 2F asan example, after being irradiated by the near-infrared lamp for onehour, the temperature within the container shielded thereby was elevatedby only about 8° C. In comparison; the temperature rise of the containershielded by the pure nylon film under the same condition was about 13.3°C., which is about 5.3° C. higher than the working example 2F. Also, thedifference of the temperature rise after one hour between the workingexample 2H and the pure nylon film is about 6.0° C.

Moreover, as can be seen from Table 2 and FIG. 3, the near-infraredtransmittance of the sample decreases as the amount of the metallicionic compound powder increases.

Together, these test results establish that the near-infrared shieldingfilm prepared from the near-infrared shielding masterbatch providedherein exhibits both the near-infrared shielding efficacy and thethermal shielding efficacy. Without being bound to any theory, it isbelieved that the near-infrared shielding film or fabric provided hereinmay reflect the irradiation from the heat source, and hence, thetemperature within the container shielded thereby is lower than that ofthe container shield by the pure nylon film.

As would be appreciated by those having ordinary skill in the art, thestability of the spinning pressure plays an important role in theviability of the spinning process. In the case when the inorganic powderagglomerates or distribute unevenly within the masterbatch, the spinningpressure of such masterbatch may increase abruptly which may causedamage to the spinning apparatus. Therefore, simulation analysis of thespinning pressure was carried out to investigate the spinnability of themasterbatch of working examples 2A to 2H and the comparative example 2provided herein.

The results of the simulation analysis of the spinning pressure revealthat after about 10 minutes of simulation, the spinning pressure of themasterbatch of the comparative example 2 was maintained at about 40bars. However, after about 20 minutes, the spinning pressure continuedto rise, and after about 35 minutes, the spinning pressure exceeded 60bars. As will occur to those with ordinary skills in the art, thevariations of the spinning pressure in connection with comparativeexample 2 preclude the use of such masterbatch in a commercializedspinning process.

In contrast, after about 5 minutes of simulation, the spinning pressureof the masterbatch of the working example 2H achieved about 40 bars, andthe pressure was relatively stable (as compared with that of thecomparative example 2) during the entire evaluation period.

Conventionally, the strong hydrogen bonds between the nylon polymerchains may result in the agglomeration of the powder within the nylonpolymer. However, the free radical compounding technique provided hereinmay facilitate the uniform distribution of the inorganic powder withinthe nylon polymer. Without being bound to any theory, it is believedthat after the compounding step, the nylon material may have aninterpenetrating network (IPN) with less hydrogen bonds, and thereby,the particles of the inorganic oxide powder may be evenly distributedtherein.

In view of the foregoing, the composition and preparation methodprovided herein not only addresses the agglomeration of the inorganicpowder within the nylon polymer, but also improves the spinnability ofthe resultant masterbatch.

Experiment 3

In Experiment 3, the masterbatch of the working example 2C was furthermade into the form of a filament and core-sheath fiber having acore/sheath ratio of about 1:1, 2:1 and 3:1, respectively. Illustratedin FIGS. 4A, 4B and 4C are optical micrographs of the cross-sections ofthe above-mentioned core-sheath fiber.

Generally, a core-sheath fiber has a core fiber and a sheath fiber. Inone example, the sheath fiber may be made of a pure nylon chip and thecore fiber may be made of the masterbatch provided herein.Conventionally, a masterbatch consisting of an inorganic powder admixedwith a nylon material is not suitable for use as the core fiber of acore-sheath fiber, because the sheath fiber made of the nylon chip maynot substantially cover such core fiber.

However, as is evidenced by the photos of FIGS. 4A to 4C, the sheathfiber according to the present working example may substantially coverthe whole outer surface of the core fiber.

The parameters of the spinning process of the Experiment 3 were: aspinning temperature of about 240-275° C.; a spinning feed speed ofabout 15-30 rpm; and a godet extension of about 2.5-2.7 folds. Theresultant fiber was then knitted into a fabric. The thermal shieldingefficacy of the knitted fabric was measured in accordance with themethod for measuring the thermal profile set forth hereinabove, and theresults thereof is illustrated in FIG. 5.

As can be seen in FIG. 5, the knitted fabrics according the embodimentsprovided herein exhibited better thermal shielding efficacies than thefabric made of pure nylon. Besides, the thermal shielding efficacies ofthe fabrics made of core-sheath fibers were more satisfactory than thefabric made of the filament. Moreover, among the fabrics made of thecore-sheath fibers, the one having a core/sheath ratio of about 3:1exhibited the best thermal shielding efficacy. Without being bound toany theory, it is speculated that during the spinning process, theparticles of the powder residing near the surface of the filament may bewore-off and the filament fiber may be damaged, thereby jeopardizing thethermal shielding efficacy thereof.

In view of the foregoing results, the near-infrared shieldingmasterbatches of working example 2C, 2F, 2G and 2H were further madeinto the form of a core-sheath conjugate fiber having a core/sheathratio of about 3:1, and the resultant fibers were further knitted. Thetemperature profiles of the knitted fabrics are illustrated in FIG. 6,and the near-infrared spectrograms (over the range of 900-2500 nm)thereof are present in FIG. 7.

FIG. 6 shows that the fabrics of the working examples provided hereinexhibited better thermal shielding efficacies as compared with thefabric made of pure nylon. Also, as can be seen in FIG. 7, the fabricsof the working examples provided herein exhibited better near-infraredshielding efficacies as compared with the fabric made of pure nylon.

The filament and core-sheath fibers of the working examples were alsoplain-woven respectively to obtain a cloth. The color fastness to waterof the cloth was determined in accordance with the protocol set forth inAATCC 61-2008 standard. The test results show that the averagediscoloration level of such fabrics is about level 4.5, which means thatthese fabrics have an adequate color fastness to water.

Moreover, the masterbatch of working example 2H was made intocore-sheath fibers having a core/sheath ratio of about 1:1, 2:1 and 3:1,respectively. The denier, tenacity, and elongation at break of thefibers were determined under test conditions in accordance with ASTMD1907-89 option 1, ASTM 1425-89 and ASTM D2256-90 option A1 standards,respectively. Test results are summarized in Table 3.

TABLE 3 Core/sheath Core/sheath Core/sheath ratio 1:1 ratio 2:1 ratio3:1 Denier/Filament (d/f) 71.1/24 69.7/24 71.1/24 Tenacity (gf/den) 3.163.03 3.0 Elongation (%) 37 35 34

Conventionally, for a fiber made of a nylon material containing about 20wt % of an inorganic material, the tenacity of such fiber is usuallyless than 2 gf/den. However, although the amount of the metallic ioniccompound powder in the masterbatch of working example 2H was about 25 wt%, the tenacity of the fiber prepared therefrom was about 3 gf/den.

Experiment 4

In Experiment 4, thermal shielding efficacy of a near-infrared shieldingpolyester film was evaluated. In this regard, the composition forpreparing the masterbatch of working example 3 is quite similar to thatof working example 1, except that polyester was used to substitute thenylon 6. Other constituents making up the composition of working example3 included: about 5 wt % of a metallic ionic compound powder (theformulation thereof was the same as that of the Experiment 1), about 1wt % of the cross-linking agent (TAIC), about 0.1 wt % of the initiator(BDK) and about 0.5 wt % of the dispersing agent (paraffin). Comparativeexample 3, on the other hand, was made of pure polyester chip. Themasterbatch was then made into the form of a film having a thickness ofabout 0.01 cm. The thermal profile of an enclosed container shielded bythe film was measured and recorded for one hour, and the results thereofare illustrated as the curve diagram of FIG. 8.

As can be seen in FIG. 8, after one hour of near-infrared irradiation,the temperature rise of the container shielded by the pure polyesterfilm was about 11.6° C.; in contrast, the temperature rise of that ofworking example was about 8.3° C.

Simulation analysis of the spinning pressure of the masterbatch ofworking example 3 was also carried out, and the simulation result showedthat this masterbatch may achieve a stable spinning pressure during thesimulation period. Hence, the masterbatch of working example 3 issuitable for use in the spinning process.

It will be understood that the above description of embodiments is givenby way of example only and that various modifications may be made bythose with ordinary skill in the art. The above specification, examplesand data provide a complete description of the structure and use ofexemplary embodiments of the invention. Although various embodiments ofthe invention have been described above with a certain degree ofparticularity, or with reference to one or more individual embodiments,those with ordinary skill in the art could make numerous alterations tothe disclosed embodiments without departing from the spirit or scope ofthis invention.

1. A method for preparing a near-infrared shielding masterbatch,comprising the steps of: providing a composition comprising: at leastone metallic ionic compound powder in an amount of about 1 wt % to about25 wt %, wherein the metallic ionic compound powder is selected from agroup consisting of barium sulfate powder, ferrious oxide powder, copperoxide powder, iridium dioxide powder, zinc oxide powder and combinationsthereof; a cross-linking agent in an amount of about 0.1 wt % to about 5wt %; a thermoplastic polymer in an amount of about 67 wt % to about98.7 wt %; an initiator in an amount of about 0.1 wt % to about 1 wt %;and a dispersing agent in an amount of about 0.1 wt % to about 2 wt %;compounding the composition at a compounding temperature of about220-270° C. for about 1 minute to about 20 minutes; and pelletizing thecompounded composition to obtain the near-infrared shieldingmasterbatch.
 2. The method of claim 1, wherein the metallic ioniccompound powder has a diameter of about 0.1 μm to about 10 μm.
 3. Themethod of claim 1, wherein the metallic ionic compound powder has adiameter of about 1 μm.
 4. The method of claim 1, wherein thecross-linking agent is a diallyl compound or a triallyl compound.
 5. Themethod of claim 4, wherein the diallyl compound is diallyl phthalate,diallyl succinate, or N,N′-diallyltartramide.
 6. The method of claim 4,wherein triallyl compound is triacryloylhexahydro-1,3,5-triazine,triallylamine, triallyl trimesate, triallyl cyanurate, triallylisocyanurate, or triallyl-ammoniumcyanurate.
 7. The method of claim 1,wherein the initiator is potassium persulfate, azobisisobutyronitrile,or benzyl dimethyl ketal.
 8. The method of claim 1, wherein thedispersing agent is selected from a group consisting of C₁₅₋₃₈ alkanes,C₁₅₋₃₈ esters, C₁₅₋₃₈ organic acids, and combinations thereof.
 9. Themethod of claim 1, wherein the thermoplastic polymer is polyester,polyamide or polypropylene.
 10. The method of claim 9, wherein thepolyester is polyethylene terephthalate, polybutylene terephthalate, orpolytrimethylene terephthalate.
 11. The method of claim 9, wherein thepolyamide is nylon 6, nylon 6.6, or nylon 6.10.
 12. The method of claim1, wherein the steps of providing the composition comprises: mixing thethermoplastic polymer and the cross-linking agent to form a firstmixture; adding the initiator into the first mixture to form a secondmixture; and adding the dispersing agent and the metallic ionic compoundpowder into the second mixture to form the composition.
 13. The methodof claim 1, further comprising mixing the composition with a 3D mixerbefore the compounding step.
 14. A near-infrared shielding masterbatch,comprising: a cross-linked thermoplastic polymer comprising athermoplastic polymer cross-linked by a cross-linking agent; and atleast one metallic ionic compound powder dispersed within thecross-linked thermoplastic polymer, wherein the metallic ionic compoundpowder is selected from a group consisting of barium sulfate powder,ferrious oxide powder, copper oxide powder, iridium dioxide powder, zincoxide powder, and combinations thereof, and a weight ratio of thecross-linked thermoplastic polymer to the metallic ionic compound powderis about 2.8:1 to about 98.8:1.
 15. The near-infrared shieldingmasterbatch of claim 14, wherein the metallic ionic compound powder hasa diameter of about 0.1 μm to about 10 μm.
 16. The near-infraredshielding masterbatch of claim 14, wherein the cross-linking agent isdiallyl phthalate, diallyl succinate, N,N′-diallyl tartramide, triallylamine, triacryloylhexahydro-1,3,5-triazine, triallyl trimesate, triallylcyanurate, triallyl isocynaurate, or triallyl-ammoniumcyanurate.
 17. Thenear-infrared shielding masterbatch of claim 14, wherein thethermoplastic polymer is polyester, polyamine, polypropylene.
 18. Thenear-infrared shielding masterbatch of claim 14, wherein thenear-infrared shielding masterbatch is made according to a methodcomprising the steps of: mixing a thermoplastic polymer of in an amountof about 67 wt % to about 98.7 wt % and a cross-linking agent in anamount of about 0.1 wt % to about 5 wt % to form a first mixture; addingan initiator in an amount of about 0.1 wt % to about 1 wt % into thefirst mixture to form a second mixture; adding a dispersing agent in anamount of about 0.1 wt % to about 2 wt % and at least one metallic ioniccompound powder in an amount of about 1 wt % to about 25 wt % into thesecond mixture to form a composition, wherein the metallic ioniccompound powder is selected from a group consisting of barium sulfatepowder, ferrious oxide powder, copper oxide powder, iridium dioxidepowder, zinc oxide powder and combinations thereof; compounding thecomposition at a compounding temperature of about 220-270° C. for about1 minute to about 20 minutes; and pelletizing the compounded compositionto obtain the near-infrared shielding masterbatch.
 19. A method forpreparing a near-infrared shielding fiber, comprising: preparing anear-infrared shielding masterbatch according to the method of claim 12;and melt spinning the near-infrared shielding masterbatch into thenear-infrared shielding fiber at a melt-spinning temperature of about180° C. to about 300° C., a masterbatch feed speed of about 5 rpm toabout 30 rpm, and a godet wheel rotate speed of about 400 m/min to about3500 m/min.
 20. The method of claim 19, wherein the melting-spinningtemperature is about 260° C. to about 270° C., and the masterbatch feedspeed is about 15 rpm to about 30 rpm.